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It was said of Cardinal Newman that he was such a good apologist that he could put the case against his own arguments better than his antagonists. Francis Spufford isn’t easily confused with Newman — ruder, less measured, much shorter sentences — but the same could be said of him. He puts the case against Christianity more intelligently than most of the people who want us not to believe. His argument is right there in the title — why Christianity, despite everything, makes surprising emotional sense — but he refuses to make little of the case against Christianity.

He goes through the arguments about whether a good and loving God can be squared with a suffering creation and he ticks off each of them in turn — no, no, no — and then baffles the reader by saying simply that none of it is convincing. We can’t make sense of it, so there. And then he goes on to say the important thing, which is that Christ, God himself, is right there in the middle of it all with us, not least in the sordid, unexceptional brutality of the crucifixion.

This disconcerting honesty peppers this entire disconcerting book. It’s a polemic for Christianity but it’s not an explanation of it.

He says of the title, Unapologetic, that he’s not trying to give a rational account of Christian beliefs. “This is a defence of Christian emotions — of their intelligibility, of their grown-up dignity … it isn’t giving an ‘apologia’, the defence of the ideas.” So he doesn’t, except in passing. What he does do is give an account of what the thing is, how it works, and as importantly, what it’s not.

Spufford’s working premise is that the existence of God is neither provable nor disprovable, so he’s not even going to try. So he concentrates on what he does know, which is the effect Christianity and the life of grace has, chiefly on him. “I assent to the ideas because I have the feelings; I don’t have the feelings because I have the ideas.”

This has a good pedigree, what with St Anselm and his notion of faith seeking understanding: “I do not seek to understand so that I can believe, but I believe so that I may understand.”

It does, however, run the risk of faith being demoted to the realm of the emotional and subjective. Except he gets there first with that too. After giving an extraordinary account of how it feels to encounter something like the presence of God in an empty church, he turns around and says it’s not like that nearly all of the time. He gives a dazzling account of the impossible impracticality of Christianity and the extent to which the institution and individual Christians fall hopelessly, disastrously, short of it — and then insists that it works, that indeed it’s the only thing that does really work.

This is a wonderful, effortlessly brilliant book. However, the author is picky — C of E, you see: he believes in the Nicene creed but isn’t sold on eternal life. But that’s in the package. He doesn’t believe in hell either. Yet what about Hopkins’s “I see the lost are like this, their curse to be as I am mine, their sweating selves, but worse”? So, not other people, but us, brought face to face with what we’ve made of ourselves? And although it’s fair enough to say that God is unprovable, it’s a cop-out not to say more about why faith isn’t unreasonable.

Actually, I part company from him in all sorts of ways. Still, there are only a couple of good Christian polemicists I can think of: Terry Eagleton, the Marxist literary critic, is one, John Waters, the Irish journalist, is another. Now we’ve got Francis Spufford. Thank God.